We have speculated that there are racial differences in contributions of various macronutrients to energy expenditure in African American and white American females. We believe there is partitioning of energy derived from fat and protein into different tissues that promote more obesity in African American than in white American females. Therefore, the main objectives of the present study are: 1. To determine the differential effects of race on carbohydrate, lipid and protein oxidation and energy expenditure(resting and postprandial) in African American and white American females with and without conjugal parents with type 2 diabetes. 2. To compare postprandial energy expenditure after carbohydrate-, fat- and protein- enriched mixed meal ingestion in African American and white American females with and without conjugal parents with type 2 diabetes and 3. To examine the relationships of fat free mass (FFM) (lean muscle mass) and visceral adiposity and substrate and energy metabolism in African American and white American females with and without conjugal parents with type 2 diabetes.